Effect of nitrogen types and the electrical conductivity of a nutrient solution on gray mold caused Botrytis cinerea on strawberry plants

남명현,이희철,김태일 충남대학교 농업과학연구소 2019 Korean Journal of Agricultural Science Vol.46 No.1

Gray mold caused by Botrytis cinerea on strawberry plants is an economically significant disease in Korea. The rates for diseased fruits are high during the strawberry harvesting period from December to February, especially in hydroponic cultivation. This study assessed the effect of the nitrogen type in the soil culture and the electrical conductivity (EC) of the nutrient solution in a hydroponic culture on the gray mold incidence in ‘Seolhyang’ strawberry plants. The nitrogen sources assayed included calcium nitrate tetrahydrate (CN4), calcium nitrate decahydrate (CN10), ammonium sulfate (AS), and commercial fertilizer 213 (213). The effect of the EC was tested at 0.5, 0.8, 1.0, and 1.5 dS · m-1. The occurrence of gray mold varied according to the nitrogen type. The disease incidence and nitrogen content for the main nitrogen type were higher compared to the non-treated control. The AS treatment showed the highest occurrence of tipburn and gray mold. The incidence of gray mold as well as the nitrogen and phosphorus content of the leaves increased as the EC level was increased. These results indicate that the incidence of gray mold in strawberry plants is related to the nitrogen content of the leaf and the EC of the nutrient solution.

태양열 소독시 유기물과 석회질소 병행 처리에 의한 딸기 시들음병균 방제

남명현,김현숙,김홍기 한국식물병리학회 2011 식물병연구 Vol.17 No.1

Field experiments were conducted to evaluate the effectiveness of soil solarization at the Nonsan Strawberry Experiment Station, Korea in 2006 and 2008. In in vitro tests, exposure times to achieve an LD_(100) of Fusarium oxysporum f. sp. fragariae were 6.6 days and 5.1 days at 45℃ and 50℃, respectively. A 100% lethal temperature was 46.7±0.1℃ for the same fungus. For field trials, solarization was conducted during the summer season using polyethylene mulch in a plastic house. The organic matter+calcium cyanamide+solarization treatment increased pH, organic matter, and calcium content compared to those before treatment in soil analysis, but no effect had an urea+solarization treatment. The temperatures at 10 cm depth were different in each treatment and the highest temperature was recorded from July 30 to August 10. The average temperature in organic matter+calcium cyanamide+solarization treatment at 10 cm depth was 3~4℃ higher than that in all the other treatments. All solarization treatments reduced the soil population of F. oxysporum f. sp. fragariae at 100% in 2008 relative to the non-treated control. All solarization treatments reduced Fusarium wilt incidence to 0% in 2006 and 2008. The effect of organic matter+calcium cyanamide+solarization against F. oxysporum f. sp. fragariae indicates that there may be future alternatives to traditional solarization for disease control as well as reducing the time needed. 유기물, 석회질소, 요소 병행처리가 딸기 시들음병의 친환경적 방제인 태양열소독의 효과 증진여부를 밝히고자 논산딸기시험장의 비닐하우스에서 2006년과 2008년에 분석하였다. 딸기에서 분리한 Fusarium oxysporum f. sp. fragariae 7개 균주의 100% 치사시간은 45℃에서 6.6일, 50℃에서는 5.1일이 소요되었고 100% 치사온도는 46.7±0.1℃로 나타났다. 태양열 소독에 의해 유기물 처리구는 처리전보다 토양내 유기물 함량이 증가하였고, 석회질소 처리구는 산도, 유기물, 칼슘 함량이 증가하였으나 요소처리구는 차이가 없었다. 태양열 소독시 지온은 처리간에 차이를 나타냈으며 7월 30일부터 8월 10일까지가 가장 높았고(48.4~54.8℃) 유기물+석회질소 처리구가 다른 처리구보다 3~4℃ 높게 유지되었다. 또한 토양내 시들음병균은 각 처리구 모두에서 사멸되었다. 시들음병 이병주율은 무처리는 2006년 20%, 2008년 13.3%의 발병율을 나타낸 반면 태양열 소독 처리구 모두에서는 시들음병 발생이 없었으며 처리간 유의성이 있었다. 따라서 딸기 시들음병 방제를 위한 유기물+석회질소를 병행한 태양열 소독 방법은 기존의 태양열소독방법을 보완하여 처리기간을 줄이면서도 효과적인 방법이 될 것이다.

딸기 설향품종의 흰가루병 건전 및 감염식물 비교 분석

남명현,전이내,이희철,이희덕,강희경 한국식물병리학회 2012 식물병연구 Vol.18 No.2

We examined the incidence of powdery mildew in strawberry cv. Seolhyang plants, and performed a comparative analysis on the temperature, photosynthesis rate, and nutrient content of healthy and powdery mildew-infected plants. Powdery mildew first infected the fruit of the strawberries in mid-January, and the disease severity increased in both fruits and leaves during the late harvest season. The rate of photosynthesis and leaf temperatures of healthy plants were higher than those of powdery mildew-infected leaves and significantly decreased with an increase in the disease severity. The healthy and powdery mildew-infected plants in the soil analysis were not significantly different in chemical compositions. The leaves of the healthy plants contained lower potassium and higher manganese and chlorophyll concentrations than the powdery mildew-infected plants. In particular, manganese was significantly higher in healthy leaves than in infected leaves. Therefore, the concentrations of potassium, manganese and chlorophyll in strawberry leaves may be an important factor for disease suppression.

전산화단층촬영술을 이용한 대장 및 직장암의 병기 결정

남명현 대한영상의학회 1988 대한영상의학회지 Vol.24 No.5

As a screening technique or for preoperative staging of the colorectal cancer the usefullness or role of CT still remains controversial. The study included retrospective analysis of 40 cases of proven colorectal cancer during last 2 years. the results were as follows.: 1. The age of patients ranged from 22 to 74 years 5th and 6th decades were over the half(52.5%) of the cases. 2. Rectum and sigmoid colon were the most frequently involved regions(23 cases 57.2%). Other areas were 9 cases of transverse colon and each 4 cases of ascending and descending colon. 3. In every cases the primary tumor was identified on CT as wall thickening. Diffuse wall thickening type was noted in 32 of 40(80%) cases. Remainings were each 4 cases of focal wall thickening type and discrete mass type. 4. Directly invaded organs were uterus (2 cases) and jejunum (1 case). 10 patients had distant metastasis and the liver were most frequent organ of involvement (9 of 10 cases). 5. Among 40 cases 34 cases were pathologically staged following surgery. CT results were compared and cor-related with modified Duke's classification. CT correctly staged 19(55.9%) and understaged 14 (41.2%) of 34 cases. 6. For the evaluation of local extension CT accuracy was 73.5% sensitivity and 50% specificity. 7. For the diagnosis of lympy node metastasis CT accuracy was 82.4% with 70% sensitivity and 100% specificity.

Taxonomic Re-evaluation of Colletotrichum gloeosporioides Isolated from Strawberry in Korea

남명현,박명수,이희덕,유승헌 한국식물병리학회 2013 Plant Pathology Journal Vol.29 No.3

For the past two decades, the causal agent of anthracnose occurring on strawberry in Korea was considered Colletotrichum gloeosporioides. However, the recent molecular analysis has shown that the genus Colletotrichum has undergone many taxonomic changes with introduction of several new species. As a result, it revealed that C. gloeosporioides indeed consisted of more than 20distinct species. Therefore, the Korean pathogen isolated from strawberry should be reclassified. The shape and size of the conidia of the pathogen were not distinctly different from those of C. gloeosporioides and C. fructicola, but it differed in shape of the appressoria. A combined sequence analysis of partial actin, glyceraldehydes-3-phosphate dehydrogenase genes, and the internal transcribed spacer regions showed that the strawberry isolates formed a monophyletic group with authentic strains of C. fructicola. On the basis of these results, the anthracnose fungi of the domestic strawberry in Korea were identified as C. fructicola and distinguished from C. gloeosporioides.

Application of an IPM-based Spray Program to Protected Cultivation of Strawberry in Korea

남명현,김현숙,이원근,성열규,마크 L. 글리슨,송정영,김홍기 한국원예학회 2008 Horticulture, Environment, and Biotechnology Vol.49 No.5

An IPM-based spray program (ISP), based on ecological and agronomic information, is necessary for reducing pesticide sprays and producing strawberries safely. In this study, the applicability of ISP to safe production of strawberries was compared with a conventional spray program (Con-SP) during the 2005-2006 and 2006-2007 seasons in plastic houses in Nonsan, Korea. The ISP program consisted of fungicide, insecticide, and miticide treatments as well as release of natural enemies before and after harvest. The ISP treatment schedule was as follows: dipping transplants in azoxystrobin before transplanting (mid-September); spraying with abamectin and thiacloprid when black mulch was applied (early October); spraying with pyraclostrobin + acetamiprid and tetraconazole + abamectin before blooming in early and mid-November, respectively; transplanting banker plants colonized by Aphidius colemani in mid-February (2005-2006 season) or November (2006-2007 season); and releasing Phytoseiulus persimilis in mid-March. Number of pesticide sprays per season for ISP and Con-SP was five and nine, respectively. Anthracnose crown rot, caused by Colletotrichum gloeosporioides, did not occur in ISP in either season, but incidence was ≤ 3.3% in Con-SP during the 2005-2006 season. Powdery mildew (Sphaerotheca aphanis var. aphanis) did not occur during harvest in ISP, but occurred during early and late harvest stages in Con-SP in both years. Incidence of Botrytis fruit rot did not differ between ISP and Con-SP. Two-spotted spider mite (Tetranychus urticae) did not appear until March in ISP; subsequently, spider mite density remained at ≤-0.5 mite per leaf until the last harvest period in both years. The number of spider mites in ISP and Con-SP during the harvest did not differ. Populations of cotton aphids (Aphis gossypii) were also higher in ISP than Con-SP but decreased from March to April, accompanied by production of aphid mummies by A. colemani. The results showed that ISP was more effective than Con-SP, and required fewer pesticide sprays.

살균제 살포횟수 감소를 위한 딸기 탄저병 방제프로그램

남명현,김홍기,N. A. Peres,김현숙,남윤규 한국식물병리학회 2011 식물병연구 Vol.17 No.3

The effect of various fungicides on anthracnose of strawberry, caused by Colletotrichum gloeosporioides, was determined in vitro, and in greenhouse and field trials. The EC_(50) values of benomyl were clearly different between two sensitive and resistant groups of isolates. Iminoctadine tris had lower EC_(50) values than mancozeb and propineb as protective fungicides and the response of mancozeb, propineb and azoxystrobin was variable depending on the isolate. In the greenhouse, pre- and post- inoculation fungicide applications significantly reduced disease compared to the non-treated control. Propineb, mancozeb and azoxystrobin were effective in controlling the disease when applied prior to inoculation. Metconazole and prochloraz-Mn treatments as ergosterol biosynthesis-inhibiting fungicides had the lowest incidence of anthracnose. In the nursery field trials in 2009 and 2010, the reduced fungicide spray program provided similar levels of disease control compared to the calendar-based applications with captan. A reduced spray program based on efficacious fungicides such as prochloraz-Mn will be useful for strawberry growers and provide more options for controlling anthracnose in Korea. Colletotrichum gloeosporioides에 의해 발생하는 딸기 탄저병에 대한 여러 살균제의 방제효과를 in vitro, 비닐하우스와 노지 육묘포장에서 검정하였다. Benomyl의 EC_(50)값은 균주 간에 저항성과 감수성 그룹으로 확연히 구별되었다. Iminoctadine tris는 mancozeb나 propineb과 같은 보호살균제보다 낮은 EC_(50)값을 보였으며 mancozeb, propineb, azoxystrobin의 효과는 균주에 따라 다양한 결과를 보였다. 비닐하우스에서, 9종의 살균제를 병원균 접종 전과 후 딸기 '설향' 품종에 처리하였을 때 모든 약제는 무처리에 비해 방제효과가 좋았다. Propineb, mancozeb, azoxystrobin은 병원균 감염 전 처리 시 방제효과가 우수했던 반면 metconazole과 prochloraz-Mn와 같은 ergosterol biosynthesis inhibiting 살균제들은 낮은 탄저병 이병율을 보였다. 2009년과 2010년 노지 육묘포장에서 감소된 살균제 처리 프로그램에 따른 탄저병 방제는 captan 처리 프로그램과 비슷한 방제효과를 보였다. 따라서 prochloraz-Mn 등과 같은 탄저병에 효과적인 살균제를 기반으로 작성된 처리 프로그램은 딸기 농가에 유용하게 사용될 수 있고 탄저병 방제를 위한 더 많은 선택을 제공할 것이다.

딸기 병걸린 식물잔재물과 토양에서 탄저병균 Colletotrichum gloeosporioides와 Glomerella cingulata의 월동과 생존

남명현,김홍기,송정영 한국식물병리학회 2004 식물병연구 Vol.10 No.3

The overwinter and survival of Colletotrichum gloeosporioides and Glomerella cingulata in strawberry tissues under field conditions was investigated in 2001 and 2002. The rates of overwinter survival in plant petiole, runner and crown were 68.7, 14.3, and 26.7%, respectively. But, under field condition, viable conidia of overwinter were not detected at the surface, 3, 5, and 10 cm depths of soil. To investigate the survival ability in soil and plant debris, C. gloeosporioides and G. cingulata isolates from strawberry were examined in laboratory and field. The viability of conidia was rapidly declined in all the treatments, with a 40% reduction in population within 10 days. In soil, the survival ability of G. cingulata conidia was similiar to that of C. gloeosporioides. The survival rate of conidia was highest under cool and dry soil conditions, and was decreased by increasing both soil temperature and moisture content. Similar results were also obtained under the condition that infected petioles were buried in soil. Results suggested that conidia as well as plant debris might be a main primary inoculum source of strawberry anthracnose.

딸기 흰가루병 방제를 위한 수확전 약제 처리 시기

남명현,정석기,김남규,유성준,김홍기 한국식물병리학회 2005 식물병연구 Vol.11 No.1

Powdery mildew, caused by Sphaerotheca aphanis var. aphanis, is an economically significant disease of strawberry in Korea. When powdery mildew is not controlled adequately, it often spreads rapidly through strawberry plants and damage is associated with reduced yields. Proper timing of fungicide applications is, therefore, essential for effective disease control. This study evaluated the efficacy by application schedule of fungicides before harvest stage for preventing powdery mildew in 2001-2003. The systemic fungicides, azoxystrobin, kresoxim-methyl, and cupper fungicide DBEDC were applied preventively during the first part of the cultivating season. Preventative applications of DBEDC by dipping treatment before transplanting and kresoxim-methyl by foliar spray before blooming stage were one of the most effective control schedule tested to prevent and manage this disease. This research demonstrated the significance of application time to control of powdery mildew, particularly provided elimination unnecessary sprays of agrochemicals and reductioncosts for strawberry growers.

딸기 탄저병 방제를 위한 정식 전 살균제 침지처리 효과

남명현,이인하,김홍기 한국식물병리학회 2014 식물병연구 Vol.20 No.1

Anthracnose crown rot (ACR), caused by Colletotrichum fructicola, is a serious disease of strawberry in Korea. The primary inoculums of ACR were symptomless strawberry plants, plant debris, and other host plants. To effectively control anthracnose in symptomless transplanted strawberries, it is necessary to use diseasefreeplants, detect the disease early, and apply a fungicide. Therefore, in 2010 and 2011, we evaluated theefficacy of pre-plant fungicide dips by using strawberry transplants infected by C. fructicola for the control ofanthracnose. Dipping plants in prochloraz-Mn for 10 min before planting was most effective for controllinganthracnose in symptomless strawberry plants and resulted in more than 76% control efficacy. Azoxystrobinshowed a control efficacy of over 40%, but plants treated with pyraclostrobin, mancozeb and iminoctadinetris showed high disease severity. The control efficacy of the dip treatment with prochloraz-Mn did not differwith temperature and time. Treatment with prochloraz-Mn for more than an hour caused growth suppressionin strawberry plants. Therefore, the development of anthracnose can be effectively reduced by dipping strawberryplants for 10 min in prochloraz-Mn before planting.